Integrated circuit, non-contact IC card, reader/writer, wireless communications method, and computer program

Abstract

An integrated circuit, a non-contact IC card, a reader/writer, a wireless communications method, and a computer program are provided to improve communication. The integrated circuit configured to execute wireless communication by means of magnetic field. The integrated circuit has a resonance circuit having resonance frequencies of a plurality of levels, a confirmation block configured to confirm whether a predetermined condition is satisfied, and a switching block configured to change the resonance frequencies if the predetermined condition is found satisfied as a result of the confirmation.

1. An integrated circuit configured to execute wireless communication by use of a magnetic field, comprising:
 a resonance circuit having resonance frequencies of a plurality of levels; 
 a confirmation block configured to confirm whether a predetermined condition is satisfied, the predetermined condition being either a predetermined count executed in the confirmation block or a predetermined period of time measured in the confirmation block; and 
 a switching block configured to change said resonance frequencies if said predetermined condition is found satisfied as a result of the confirmation. 
 
     
     
       2. A non-contact integrated circuit card comprising an integrated circuit as set forth in  claim 1 . 
     
     
       3. An information processing terminal comprising an integrated circuit as set forth in  claim 1 . 
     
     
       4. A card reader/writer comprising an integrated circuit as set forth in  claim 1 . 
     
     
       5. A wireless communications method based on an integrated circuit having a resonance circuit having resonance frequencies of a plurality of levels, comprising the steps of:
 confirming whether a predetermined conditions is satisfied, the predetermined condition being either a predetermined count or a predetermined period of time; and 
 changing said resonance frequencies by switching between said resonance frequencies if said predetermined condition is found satisfied. 
 
     
     
       6. A computer memory storing a computer program configured to control an integrated circuit having resonance frequencies of a plurality of levels, comprising the processes of:
 confirming whether a predetermined conditions is satisfied, the predetermined condition being either a predetermined count or a predetermined period of time; and 
 changing said resonance frequencies by switching between said resonance frequencies if said predetermined condition is found satisfied. 
 
     
     
       7. An integrated circuit configured to execute wireless communication by use of a magnetic field, comprising:
 a resonance circuit having resonance frequencies of a plurality of levels; 
 a confirmation block configured to confirm whether a predetermined condition is satisfied, the predetermined condition being a predetermined count executed in the confirmation block; and 
 a switching block configured to change said resonance frequencies if said predetermined condition is found satisfied as a result of the confirmation. 
 
     
     
       8. An integrated circuit configured to execute wireless communication by use of a magnetic field, comprising:
 a resonance circuit having resonance frequencies of a plurality of levels; 
 a confirmation block configured to confirm whether a predetermined condition is satisfied, the predetermined condition being a predetermined period of time measured in the confirmation block; and 
 a switching block configured to change said resonance frequencies if said predetermined condition is found satisfied as a result of the confirmation. 
 
     
     
       9. An integrated circuit configured to execute wireless communication by use of a magnetic field, comprising:
 a resonance circuit having resonance frequencies of a plurality of levels; 
 a confirmation block configured to confirm whether a predetermined condition is satisfied; 
 a switching block configured to change said resonance frequencies if said predetermined condition is found satisfied as a result of the confirmation; and 
 a capacitor having capacitances of a plurality of levels, said switching block switching between said capacitances to change said resonance frequencies. 
 
     
     
       10. An integrated circuit configured to execute wireless communication by use of a magnetic field, comprising:
 a resonance circuit having resonance frequencies of a plurality of levels; 
 a confirmation block configured to confirm whether a predetermined condition is satisfied; 
 a switching block configured to change said resonance frequencies if said predetermined condition is found satisfied as a result of the confirmation; and 
 an inductor having inductances of a plurality of levels, said switching block switching between said inductances to change said resonance frequencies.